Green synthesis of silver nanoparticles using Silybom marianum extract (SME@AgNPs) and its antibacterial activity against gram positive and gram negative bacteria

A simple, fast and cost-effective process to synthesis of silver nanoparticles (SME@AgNPs) with very favorable efficiency in biological assay has been expanded utilizing Silybom marianum (S. marianum) extract as capping and reducing agent. Various parameters like AgNO۳ concentration, temperature, pH and contact time on the morphology and size of SME@AgNPs were investigated to reach optimum condition. The as-synthesized SME@AgNPs were characterized using Fourier-transform infrared spectroscopy (FT-IR), (X-ray powder diffraction (XRD), Field emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDS) and ultraviolet-visible spectroscopy (UV-Vis) techniques. FE-SEM images illustrated that the particles were spherical in morphology and well dispersed with the average particle diameter of ۴۵-۶۰ nm. The as-prepared SME@AgNPs illustrated efficient antibacterial activity against Klebsiella pneumoniae (K. pneumoniae; ATCC ۷۰۰۶۰۳), Staphylococcus aureus (S. aureus; ATCC ۱۶۵۳۸) and Escherichia coli (E. coli, ATCC ۲۵۹۲۲) bacteria. The results show that as-synthesized SME@AgNPs showed a significant inhibitory effect against different bacteria, where the minimum inhibitory concentration (MIC) values of ۴.۶ and ۱۸.۷۵ and ۱۸.۷۵ μg/ml were obtained for prepared silver nanoparticles against E. coli, K. pneumoniae and S. aureus, respectively.

Keywords:

Green synthesis , Silybom marianum , AgNPs , Antibacterial activity